Preparation of polyphenylene ether/polyamide molding materials

Abstract

In order to prepare thermoplastic molding materials of A) 5-95% by weight of a modified polyphenylene ether, B) 5 to 95% by weight of a thermoplastic polyamide, C) 0 to 25% by weight of an impact-modifying rubber, and D) 0 to 50% by weight of auxiliaries and/or additives, the components A and B and if necessary the components C and D are fed individually at one or more points into an extruder, mixed with one another, and melted. The component A present in a pulverulent consistency is compacted and/or sintered under pressure and if necessary with the addition of heat, preferably at a pressure corresponding to a nip pressure of 1 to 100 kn/cm to form a porous compact before it is fed into the extruder. The compact is then modified and added as granules to the feed zone of the extruder. In this way the proportion of the fines in the polyphenylene ether is considerably reduced, so that there is virtually no further danger of dust explosions. Further advantages include an improved ease of metering and reduced electrostatic charge.

We claim: 
     
       1. A process for preparing a thermoplastic molding material of A) 5-95% by weight of a polyphenylene ether,   B) from 5 to 95% by weight of a thermoplastic polyamide,   C) from 0 to 25% by weight of an impact-modifying rubber, and   D) from 0 to 50% by weight of additives, in which the components are fed individually at one or more points into an extruder, mixed with one another, and melted, and the molten mixture is extruded, wherein component A is subjected to at least one process selected from the group consisting of compacting and sintering under pressure to form a porous compact, and the porous compact is added as granules to the feed zone of the extruder.     
     
     
       2. A process as claimed in claim 1, wherein component A is subjected to at least one process selected from the group consisting of compacting and sintering at from about 10° C. to about 150° C. and at a pressure corersponding to a nip pressure of from 1 to 100 kN/cm. 
     
     
       3. The process of claim 1, wherein heat is added to component A during the formation of the porous compact.